Background

Despite great progress in antiviral treatments, hepatitis B virus (HBV) infection is still a major global public health problem. Approximately 2 billion people have been infected worldwide during their lifetime, and more than 350 million are chronic carriers of the virus. HBV infection may cause acute and chronic hepatitis, which leads to incurable chronic liver problems and cancer. Current HBV vaccines on the market, which protect most people against HBV infection, contain only the S antigen. However, almost 5-10% people vaccinated with the available vaccines fail to mount an adequate antibody response to offer protection. This raises a dire need to develop novel and efficient prophylactic or therapeutic vaccines for HBV infection with lower nonresponse rates.